invoke.texi (align-threshold, [...]): Document.

	* invoke.texi (align-threshold, align-loop-iterations): Document.
	* final.c: Include cfgloop.h, params.h
	(compute_alignments): Dump decisions and compare them with loop
	structure; honor given parameters.
	(pass_compute_alignments): New dump file.
	* params.def (PARAM_ALIGN_THRESHOLD, PARAM_ALIGN_LOOP_ITERATIONS): New.
	* Makefile.in (final.o): Add dependency on cfgloop.h and params.h

From-SVN: r129162

1 files changed, 49 insertions, 6 deletions

diff --git a/gcc/final.c b/gcc/final.c
index b59a222..654f847 100644
--- a/gcc/final.c
+++ b/gcc/final.c
@@ -78,6 +78,8 @@ along with GCC; see the file COPYING3.  If not see
 #include "df.h"
 #include "vecprim.h"
 #include "ggc.h"
+#include "cfgloop.h"
+#include "params.h"
 
 #ifdef XCOFF_DEBUGGING_INFO
 #include "xcoffout.h"		/* Needed for external data
@@ -673,6 +675,8 @@ compute_alignments (void)
 {
   int log, max_skip, max_log;
   basic_block bb;
+  int freq_max = 0;
+  int freq_threshold = 0;
 
   if (label_align)
     {
@@ -688,6 +692,19 @@ compute_alignments (void)
   if (! optimize || optimize_size)
     return 0;
 
+  if (dump_file)
+    {
+      dump_flow_info (dump_file, TDF_DETAILS);
+      flow_loops_dump (dump_file, NULL, 1);
+      loop_optimizer_init (AVOID_CFG_MODIFICATIONS);
+    }
+  FOR_EACH_BB (bb)
+    if (bb->frequency > freq_max)
+      freq_max = bb->frequency;
+  freq_threshold = freq_max / PARAM_VALUE (PARAM_ALIGN_THRESHOLD);
+
+  if (dump_file)
+    fprintf(dump_file, "freq_max: %i\n",freq_max);
   FOR_EACH_BB (bb)
     {
       rtx label = BB_HEAD (bb);
@@ -697,7 +714,12 @@ compute_alignments (void)
 
       if (!LABEL_P (label)
 	  || probably_never_executed_bb_p (bb))
-	continue;
+	{
+	  if (dump_file)
+	    fprintf(dump_file, "BB %4i freq %4i loop %2i loop_depth %2i skipped.\n",
+		    bb->index, bb->frequency, bb->loop_father->num, bb->loop_depth);
+	  continue;
+	}
       max_log = LABEL_ALIGN (label);
       max_skip = LABEL_ALIGN_MAX_SKIP;
 
@@ -708,6 +730,18 @@ compute_alignments (void)
 	  else
 	    branch_frequency += EDGE_FREQUENCY (e);
 	}
+      if (dump_file)
+	{
+	  fprintf(dump_file, "BB %4i freq %4i loop %2i loop_depth %2i fall %4i branch %4i",
+		  bb->index, bb->frequency, bb->loop_father->num,
+		  bb->loop_depth,
+		  fallthru_frequency, branch_frequency);
+	  if (!bb->loop_father->inner && bb->loop_father->num)
+	    fprintf (dump_file, " inner_loop");
+	  if (bb->loop_father->header == bb)
+	    fprintf (dump_file, " loop_header");
+	  fprintf (dump_file, "\n");
+	}
 
       /* There are two purposes to align block with no fallthru incoming edge:
 	 1) to avoid fetch stalls when branch destination is near cache boundary
@@ -720,12 +754,14 @@ compute_alignments (void)
 	 when function is called.  */
 
       if (!has_fallthru
-	  && (branch_frequency > BB_FREQ_MAX / 10
+	  && (branch_frequency > freq_threshold
 	      || (bb->frequency > bb->prev_bb->frequency * 10
 		  && (bb->prev_bb->frequency
 		      <= ENTRY_BLOCK_PTR->frequency / 2))))
 	{
 	  log = JUMP_ALIGN (label);
+	  if (dump_file)
+	    fprintf(dump_file, "  jump alignment added.\n");
 	  if (max_log < log)
 	    {
 	      max_log = log;
@@ -736,10 +772,13 @@ compute_alignments (void)
 	 align it.  It is most likely a first block of loop.  */
       if (has_fallthru
 	  && maybe_hot_bb_p (bb)
-	  && branch_frequency + fallthru_frequency > BB_FREQ_MAX / 10
-	  && branch_frequency > fallthru_frequency * 2)
+	  && branch_frequency + fallthru_frequency > freq_threshold
+	  && (branch_frequency
+	      > fallthru_frequency * PARAM_VALUE (PARAM_ALIGN_LOOP_ITERATIONS)))
 	{
 	  log = LOOP_ALIGN (label);
+	  if (dump_file)
+	    fprintf(dump_file, "  internal loop alignment added.\n");
 	  if (max_log < log)
 	    {
 	      max_log = log;
@@ -749,12 +788,15 @@ compute_alignments (void)
       LABEL_TO_ALIGNMENT (label) = max_log;
       LABEL_TO_MAX_SKIP (label) = max_skip;
     }
+
+  if (dump_file)
+    loop_optimizer_finalize ();
   return 0;
 }
 
 struct tree_opt_pass pass_compute_alignments =
 {
-  NULL,                                 /* name */
+  "alignments",                         /* name */
   NULL,                                 /* gate */
   compute_alignments,                   /* execute */
   NULL,                                 /* sub */
@@ -765,7 +807,8 @@ struct tree_opt_pass pass_compute_alignments =
   0,                                    /* properties_provided */
   0,                                    /* properties_destroyed */
   0,                                    /* todo_flags_start */
-  0,                                    /* todo_flags_finish */
+  TODO_dump_func | TODO_verify_rtl_sharing
+  | TODO_ggc_collect,                   /* todo_flags_finish */
   0                                     /* letter */
 };